UNITED NATIONS (CNN) -- Responding to Iraq's admission that it had moved sensitive equipment -- and on a day when three more inspection teams were prevented from entering Iraqi weapons sites -- the U.N. Security Council politely urged Iraq to comply with all resolutions on disarmament.

Although it did not condemn Iraq, the council said it should "comprehensively implement relevant resolutions." In a carefully worded statement, the council said it "hopes
that any recurrence" of resolution violations "will be avoided" because they were "not in conformity" with U.N. orders.

While the Security Council seemed to go out of its way not to give offense, British Ambassador Sir John Weston was not so circumspect. He called the Iraqi tampering with U.N. monitoring equipment "completely unacceptable."

Chief U.N. weapons inspector Richard Butler said Wednesday that Iraq had taken advantage of a halt in weapons inspections to disable surveillance cameras and hide key
equipment from sites being monitored by U.N. weapons inspectors. (
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Butler said the situation is "very serious" and that the Iraqis could use some of the equipment that had been under surveillance to "produce seed stocks of biological warfare agent."

"They've turned the lights off and it's pretty hard to take
pictures when you've got no lights," Butler told CNN Thursday. "In other places, they've simply obstructed the cameras, put bags over the lenses. It looks a little bit like, 'the cat's away, the mice will play.'"

Iraq admits it moved equipment

Iraq acknowledged Thursday that it had moved the equipment saying it feared the equipment would be damaged in an air strike. Iraq said it would return the equipment when the threat had passed. But it denied that it had tampered with cameras, although it did say one was destroyed during a test.

In a letter to the U.N., Iraqi Foreign Minister Mohammed Saeed al-Sahaf said that Iraq was preparing for what it called U.S.-led military aggression and wanted the machinery out of harm's way. Speaking to reporters, Iraqi Deputy Prime Minister Tariq Aziz added, "We expect them to attack us with warplanes and missiles. It's only natural to safeguard our equipment."

Aziz also accused Butler of making "a deliberate attempt to blackmail the Security Council and escalate the situation." In an interview with CNN, Butler called the allegation "ludicrous."

The foreign minister described the movement of equipment as temporary and said it would not be used in any prohibited way. "We are going to put the equipment back to its previous positions ... and we will invite U.N. monitoring teams to see it and be sure about it," Al-Sahaf said.

3 more inspection teams blocked

Three U.N. inspection teams -- one specializing in missiles, another in biological warfare and the third in chemical weapons -- were blocked for the fourth straight day from entering Iraqi weapons sites Thursday. They were told that they could enter the sites only if the American members of the teams left.

The inspectors turned back after the team chiefs "informed the Iraqi authorities that what they are doing is considered a clear violation of the cease-fire agreements," the spokesman said.

Thursday's developments came as three U.N. envoys met again with Baghdad officials about Iraq's defiance of terms that led to the 1991 Gulf War cease-fire. U.N. spokesman Fred
Eckhard said the envoys had completed their substantive talks and would return to New York on Friday after a brief, informal meeting.

The ambassadors of Russia, China and Poland and the charges d'affaires of France and Egypt took part in the talks Thursday. Since the U.S. and Iraq do not have official diplomatic relations, the Polish diplomat represents the U.S. interests in Iraq.

The leading envoy, Lakhdar Brahimi of Algeria, said late
Thursday that Iraqi officials had covered "all the
subjects Iraq wants to be delivered to the U.N. Secretary-General, and we will do that."

U.S. carrier's port call delayed

The envoys are trying to persuade Iraq to revoke its order
expelling Americans members of the U.N. weapons monitoring teams. Iraq is trying to use the meetings to press for an end to the U.N. economic sanctions.

Iraq says American members of the weapons inspection teams are preventing Iraq's certification and wants them out of the country.

If the Security Council were to declare Iraq in "material breach" of the cease-fire, it could pave the way for military action. Diplomatic sources told CNN that military action seemed likely unless the Iraqi position changes.

Pentagon officials acknowledged that the threat of military strikes against Iraq is real, but there were no indications the United States and it allies are preparing to attack Iraq in the immediate future.

However, sources in the Pentagon say that the aircraft carrier USS Nimitz will delay a scheduled port call in the United Arab Emirates lest it be interpreted by the Iraqis as a sign of weakness.

The Nimitz, and its escort, the USS Port Royal, a cruiser equipped with Tomahawk cruise missiles, were to have arrived in port on Saturday for a five-day visit.

The absence of the Nimitz and the Port Royal would have left six U.S. warships within striking distance of Iraq, but the Pentagon decided that during the present U.N.-Iraq stalemate it would be best to leave the ships where they are.

Turkish paper says U.S. wants to use air base

Also Thursday, the Turkish daily Hurriyet quoted Prime Minister Mesut Yilmaz as saying the United States has asked Turkey to allow the use of an air base for possible air raids against Iraq.

Yilmaz said Turkey has not replied and was waiting to see what decisions are taken by the Security Council.

U.S. military officials repeatedly have said the United States would seek an international consensus to respond to Iraq's defiance. "The United Nations has a series of things it could recommend," including additional economic sanctions or a military response, U.S. Defense Secretary William Cohen said in Washington.